The objectives and specific aims of this proposal are to develop improved assays for both the detection of antibodies against HTLV-I, HTLV-II and HIV-2 antigens and also the detection, characterization, and quantification of the proteins and nucleic acids of these same viruses. All assays will make use of previously accrued and well-characterized bank of over 20,000 human sera and cells to facilitate assessment of sensitivity and specificity. Serological assays will be designed to detect either IgG or IgM reactivities. Assay formats will involve a variety of sources of viral antigen including purified virions, synthetic peptides and recombinant proteins. The aim will be to develop ELISA, western blots and/or immunoblots that are sensitive and specific enough to obviate the need for RIPA's. Protein detection will center on the development of polyclonal and monoclonal antibodies to be used in direct cell staining or antigen capture assay formats. Antibodies will be made against all major structural, functional, and regulatory viral proteins. Nucleic acid studies will center on the continued development of the PCR and QB replicase system for the detection, quantification and sequencing of specific viral DNA and RNA from human tissues and body fluids. It is anticipated that the above techniques will make their way into clinical systems for the prevention, diagnosis and treatment of human retroviral disorders.